Calcium Dependent Protein Kinase 1 as a drug target for T. gondii and C. parvum

钙依赖性蛋白激酶 1 作为弓形虫和微小弯曲菌的药物靶点

基本信息

批准号：
8097594
负责人：
ETHAN A MERRITT
金额：
$ 101.31万
依托单位：
UNIVERSITY OF WASHINGTON
依托单位国家：
美国
项目类别：
财政年份：
2010
资助国家：
美国
起止时间：
2010-07-01 至 2015-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8097594
关键词：
Active Sites Affinity Animal Disease Models Animal Model Animals Binding Binding Sites Bioavailable Biological Assay Cell Culture Techniques Cells Chemicals Complex Consumption Cryptosporidiosis Cryptosporidium Cryptosporidium parvum Data Development Disease Drug Delivery Systems Drug Kinetics Evaluation Food Gatekeeping Homologous Gene Human Infection Invaded Knowledge Lead Libraries Ligands Light Mammalian Cell Mus Organism Parasites Pharmaceutical Preparations Phosphotransferases Positioning Attribute Process Property Protein Kinase Proteins Protozoa Relative (related person)Resistance Side Structure Synthesis Chemistry Toxic effect Toxoplasma Toxoplasma gondii Toxoplasmosis Water Work analog base calcium-dependent protein kinase design follow-up inhibitor/antagonist kinase inhibitor meetings mutant novel therapeutics obligate intracellular parasite pre-clinical scaffold

项目摘要

DESCRIPTION (provided by applicant): New therapeutics are needed for infections caused by Cryptosporidium parvum and Toxoplasma gondii. Calcium dependent protein kinase 1 (CDPK1) of T. gondii is thought to be critical for the invasion process of T. gondii and thus is a drug target for toxoplasmosis. By inference, the homologous CDPK of C. parvum is likely to be critical for infection by cryptosporidium. We have solved the crystal structures of TgCDPK1 and CpCDPK1 and have shown the active sites are susceptible to "bumped" kinase inhibitors (BKI) that do not inhibit mammalian kinases. This differential sensitivity is due to the absence of a bulky gatekeeper side chain in the ATP binding site of both TgCDPK1 and CpCDPK1 that is present in mammalian protein kinases. Thus, these BKI offer tremendous selectivity for inhibition of TgCDPK1 & CpCDPK1 vs. human kinases. Furthermore, BKI compounds have shown minimal toxicity in mice when administered in the course of other work. Our preliminary results show that multiple BKI compounds based on a known scaffold can inhibit TgCDPK1 & CpCDPK1 and also inhibit T. gondii and C. parvum cell invasion at low-mid nanomolar concentrations. Expression of a mutant TgCDPK1 with a Met gatekeeper in T. gondii cells leads to resistance to the BKI effect, demonstrating the BKI inhibits cell entry via CDPK1. We will develop compounds that are orally bioavailable, sufficiently potent, lack toxicity, and cure animal models of T. gondii and/or C. parvum. By the end of this project we expect to identify and characterize 2 to 4 leads for evaluation as potential drugs for cryptosporidiosis and toxoplasmosis. This project will initiate development of new drugs to treat diseases caused by two parasitic protozoa, Cryptosporidium and Toxoplasma that are commonly transmitted by consumption of impure food or water. We have identified a class of chemical compounds that specifically inhibit a particular protein used by these parasites to invade human cells. We will design and characterize compounds of this class that are nontoxic to humans but effective in treating infection. Relevance: This project will initiate development of new drugs to treat diseases caused by two parasitic protozoa, Cryptosporidium and Toxoplasma, that are commonly transmitted by consumption of impure food or water. We have identified a class of chemical compounds that specifically inhibit a particular protein used by these parasites to invade human cells. We will design and characterize compounds of this class that are nontoxic to humans but effective in treating infection.

描述（由申请人提供）：由隐孢子虫和弓形虫引起的感染需要新的治疗剂。 T. gondii的钙依赖性蛋白激酶1（CDPK1）被认为对于gondii的浸润过程至关重要，因此是弓形虫病的药物靶标。通过推断，孢子虫的同源CDPK可能对隐孢子虫感染至关重要。我们已经解决了TGCDPK1和CPCDPK1的晶体结构，并表明活性位点易受不抑制哺乳动物激酶的“颠簸”激酶抑制剂（BKI）。这种差异敏感性是由于在哺乳动物蛋白激酶中存在的TGCDPK1和CPCDPK1的ATP结合位点中缺乏笨重的守门人侧链。因此，这些BKI对抑制TGCDPK1和CPCDPK1与人类激酶具有极大的选择性。此外，在其他工作过程中给药时，BKI化合物在小鼠中显示出最小的毒性。我们的初步结果表明，基于已知支架的多种BKI化合物可以抑制TGCDPK1和CPCDPK1，并且还抑制低中间纳摩尔浓度下的T. gondii和C. parvum细胞浸润。 T. gondii细胞中具有MET守门人的突变型TGCDPK1的表达会导致对BKI效应的抗性，证明BKI通过CDPK1抑制了细胞的进入。我们将开发出口服生物利用，足够有效，缺乏毒性的化合物，并治愈T. gondii和/或C. parvum的动物模型。到该项目结束时，我们希望识别并表征2至4个铅评估是隐孢子虫病和弓形虫病的潜在药物。该项目将启动开发新药物，以治疗由两个寄生原生动物，隐孢子虫和弓形虫引起的疾病，这些疾病通常是由于食用不纯净的食物或水而传播的。我们已经确定了一类化合物，这些化合物专门抑制这些寄生虫侵入人类细胞的特定蛋白质。我们将设计和表征该类别的化合物，这些化合物对人类无毒，但可有效治疗感染。相关性：该项目将启动开发新药物，以治疗由两个寄生原生动物，隐孢子虫和弓形虫引起的疾病，这些疾病通常是由于食用不纯净的食物或水而传播的。我们已经确定了一类化合物，这些化合物专门抑制这些寄生虫侵入人类细胞的特定蛋白质。我们将设计和表征该类别的化合物，这些化合物对人类无毒，但可有效治疗感染。